I have no car at the moment, which means I have no way to get to the next pet shop to pick up some aquarium salt for my sick fish. I opted to buy some natural, non-iodised sea salt from the supermarket - it said on the pack that its made for preserving things and curing wounds, etc.
Will this be okay for my betta?
If so, how much do i use for a 3.5 gallon tank?
Thankyou in advanced :'D

I wouldn't risk using the sea salt on him. Is there any taxi services in the area? I know they are expensive but I used to have to taxi to my petstore as well all the time it sucked. I would try to find a way to the petstore if you can. Just in case